Index: Lib/imaplib.py
===================================================================
--- Lib/imaplib.py	(revision 88239)
+++ Lib/imaplib.py	(working copy)
@@ -22,7 +22,7 @@
 
 __version__ = "2.58"
 
-import binascii, errno, random, re, socket, subprocess, sys, time
+import binascii, errno, random, re, socket, subprocess, sys, time, calendar
 
 try:
     import ssl
@@ -1340,22 +1340,12 @@
         zone = -zone
 
     tt = (year, mon, day, hour, min, sec, -1, -1, -1)
+    utc = calendar.timegm(tt) - zone
 
-    utc = time.mktime(tt)
+    return time.localtime(utc)
 
-    # Following is necessary because the time module has no 'mkgmtime'.
-    # 'mktime' assumes arg in local timezone, so adds timezone/altzone.
 
-    lt = time.localtime(utc)
-    if time.daylight and lt[-1]:
-        zone = zone + time.altzone
-    else:
-        zone = zone + time.timezone
 
-    return time.localtime(utc - zone)
-
-
-
 def Int2AP(num):
 
     """Convert integer to A-P string representation."""
Index: Lib/test/test_imaplib.py
===================================================================
--- Lib/test/test_imaplib.py	(revision 88239)
+++ Lib/test/test_imaplib.py	(working copy)
@@ -36,6 +36,23 @@
             b'25 (INTERNALDATE "31-Dec-1999 12:30:00 -1130")')
         self.assertEqual(time.mktime(tt), t0)
 
+        # Test for DST-related bug (issue 10941)
+        if 'TZ' in os.environ:
+            saved_tz = os.environ['TZ']
+        else:
+            saved_tz = None
+        os.environ['TZ'] = 'MST+07MDT,M4.1.0,M10.5.0'
+        time.tzset()
+        self.assertNotEqual(imaplib.Internaldate2tuple(
+            b'25 (INTERNALDATE "02-Apr-2000 02:30:00 +0000")'),
+                            imaplib.Internaldate2tuple(
+            b'25 (INTERNALDATE "02-Apr-2000 03:30:00 +0000")'))
+        if saved_tz == None:
+            del os.environ['TZ']
+        else:
+            os.environ['TZ'] = saved_tz
+        time.tzset()
+
     def test_that_Time2Internaldate_returns_a_result(self):
         # We can check only that it successfully produces a result,
         # not the correctness of the result itself, since the result